Collapsible container



April 28, 1954 w. E. OAKEY ETAL 3,130,850

coLLAPsIBLE CONTAINER 4 Sheets-Sheet 1 Filed Au 24, 1961 J dwJdfgm P/K f a ee /oe av i Z M W d Z; WM; B MW April 28, 1964 w. E. OAKEY ETAL 3,

COLLAPSIBLE CGNTAINER Filed Aug. 24, 1961 4 Sheebs-Sheet s April 28, I964 w. E. OAKEY ETAL cmmAPsIBLE:

4 She sets-Sheet: 4

Filed Aug, 24, 1.961.

United States Patent 3,130,850 CULLAFSHELE 0NTAENER William E. Oaliey, Etheliaert J. Baker, .lra, and Willis L. Myriatt, San Antonio, Tex., and .lunius W. Millard, 16 Alder Lane, and Norman Weisherg, 12 Karal Drive, both of Framingharn, Mass; said flake, said Baker, and said Mynatt, assiguors to Southwest Research Institute, San Antonio, Tex., a trust estate Filed Aug. 24, 196i, Ser. No. 133,720 16 (Claims. tCl. 220-6) This invention relates to collapsible containers of the type having fluid-tight, inner, flexible liners disposed within collapsible outer shells.

In presently known collapsible reusable containers of this type, the inner liners often are pinched, cut or otherwise subjected to mechanical damage during collapsing of the outer shell thereby making it necessary to repair or replace the liners before the containers can be put back into service. As a result of this tendency of the container liners to become damaged during collapsing operations, these presently known collapsible containers generally are considered unsatisfactory, not only because of the time and expense involved in repairing or replacing the damaged liners, but also because the containers can be dangerous if used in many important applications. For example, in some cases it may not be possible or at least not practical to make necessary repairs to or replacement of the damaged liners before the containers are placed back in service. In such cases, leakage of material from the damaged container liners may create serious hazards to persons and property, particularly when the containers are being used to handle flammables, explo sives, corrosives, poisons, and the like.

An object of this invention is to provide a collapsible container which obviates the foregoing difiiculties and disadvantages.

Another object of the invention is to provide an improved collapsible container of the type having an inner fluid-tight liner which is constructed so that the likelihood of the inner liner being cut, pinched or otherwise damaged during collapsing and erecting operations is substantially reduced or even eliminated from a practical point of view.

Another object of the invention is to provide an improved collapsible container of the type having an inner liner disposed Within a collapsible outer shell in which the inner liner is at all times protectively surrounded by the outer shell structure, even during collapsing and erecting operations.

Another object of the invention is to provide an improved reusable container according to the foregoing objects which is rigid and extremely sturdy when in its erect operative position for handling various -materials, yet which can be quickly and easily collapsed and erected, when empty, without damaging the container inner liner and without swinging any of the panels of the container outer shell outwardly of the positions these panels normally occupy when the container is in its erect operative condition.

Another object of the invention is to provide a reusable container having a fluid-tight inner liner mounted within a collapsible outer shell structure in which the walls of the inner liner are caused, when the liner is emptied, first to be collapsed inwardly on one another to predetermined positions within the erect outer shell structure, and then, upon movement of one wall of the shell structure from its erect operative position to its collapsed inoperative position, to be folded in a smooth, orderly manner into a protective cavity formed in the bottom of the shell struc ture.

Another object of the invention is to provide an improved collapsible container of the type mentioned in the 3,130,850 Patented Apr. 28, 1964 foregoing objects in which the base for supporting the container also is made collapsible.

Another object of the invention is to provide an improved inner liner for use in collapsible reusable containers of the type mentioned in the foregoing objects.

Other objects, advantages and features are inherent and will become apparent upon consideration of the specification, claims and attached drawings.

In the attached drawings, there is illustrated one embodiment of a collapsible container with which the foregoing and other objects and advantages may be accomplished. In these drawings, wherein like characters of reference are used to designate like parts throughout the several views:

FIG. 1 is a perspective view of a collapsible container constructed according to this invention and shows the container in its erect operative condition;

FIG. 2 is a view similar to FIG. 1 except that the container is shown in its collapsed inoperative condition;

FIGS. 3, 4, 5 and 6 represent the collapsible container of FIG. 1 and illustrate the manner in which the front, rear and end wall panels of the container outer shell are sequentially swung about their various hinged connections between their erect operative positions and their collapsed inoperative positions;

FIG. 7 is an enlarged view taken along the line 77 of FIG. 1;

FIG. 8 is an enlarged view taken along the line 88 of FIG. 2, the inner bladder of the container having been omitted;

FIG. 9 represents an enlarged fragmentary view of the outer surface of the right hand end panel of the container of FIG. 1 and shows the intermediate hinge of the panel in its partially opened FIG. 5 position;

FIG. 10 is an enlarged View of a portion of the inner surface of the hinge shown in FIG. 9;

FIG. 11 is an enlarged cross sectional view taken along the line 11-41 of FIG. 9;

FIG. 12 is a view of the interior portion of the collapsible container of FIG. 1 as seen from the right hand side of the container and shows the container inner bladder in the position it first assumes when emptied and collapsed within the erect container outer shell;

FIG. 13 is a rear view of the container shown in FIG. 12 and illustrates by a series of dotted lines the manner in which the end walls of the collapsed bladder are buckled inwardly toward one another as the front panel of the container outer shell is swung from its erect operative position to its collapsed inoperative position;

FIG. 14 is a perspective view of the collapsed bladder of FIG. 12 removed from the container outer shell, the erect positions of the top, rear and end walls of the bladder being shown in dotted lines; and

FIG. 15 is an enlarged cross sectional view taken along the line 15-15 of FIG. 1.

Referring now to the drawings, it will be seen that the collapsible outer shell of the container of this invention embodies a plurality of hingedly interconnected rectilinear panels including front and rear wall panels 20 and 21, end wall panels 22 and 23, and top and bottom wall panels 24 and 25, respectively. These outer shell panels preferably are made of rigid material such as metal, plastic, or the like, the front, rear, top and bottom wall panels being of unitary construction, and the end wall panels being hinged intermediate their ends. Bottom Wall panel 25 is formed in the shape of a shallow pan and has relatively low upstanding rigid Walls 26, 27, 28 and 29 made integral therewith near its front, rear and opposed end edges, respectively, said upstanding walls defining the lateral extent of an open topped cavity 30 formed on the top side of bottom panel 25.

Means are provided for hingedly connecting the several panels of the container outer shell in such a manner that the unitary front and rear panels and the intermediately hinged end panels may be swung in predetermined sequence between vertical operative positions and horizontal inoperative positions folded inwardly and stacked in predetermined order between said top and bottom panels. More particularly, front and read panels and 21 are hingedly connected at their lower ends, as by vertically swingable hinges 31 and 32, with the tops of the upstanding front and rear walls 26 and 27, respectively, of bottom panel 25, While intermediately hinged end panels 22 and 23 are hingedly connected at their lower ends, as by vertically swingable hinges 33 and 34, with the tops of the upstanding opposed end walls 25% and 2 respectively, of bottom panel 25 and are hingedly connected at their upper ends, as by vertically swingable hinges 35 and 36, with top panel 24 near its opposed end edges. The upstanding front wall 26 of bottom panel 25 to which front wall panel 20 is hinged is lower than upstanding rear wall 27 to which rear wall panel 21 is hinged, rear wall 27 in turn being lower than the equally sized upstanding end walls 28 and 2? of bottom panel 25 to which end wall panels 22 and 23 are hinged.

Thus, as is illustrated in FIGS. 3-6, in order to properly collapse the container outer shell, it is necessary first to swing front panel 2% inwardly on its hinge 31 between the vertically positioned rear and end panels from its vertical position to its horizontal position stacked above bottom panel 25. Next, rear panel 21 must be swung inwardly on its hinge 32 between the vertically positioned end panels from its vertical position to its horizontal po sition stacked on top of front panel 26 Finally, end panels 22 and 23 may be simultaneously swung or rotated about their respective end hinges 33, 34, 353' and 36 and about their respective intermediate hinges 37 and 38 from their vertical positions to their horizontal positions buckled inward toward one another and stacked side by side between top panel 24 and rear panel 21.

The container outer shell may be erected by reversing the foregoing steps. That is, in order to erect the outer shell, it is necessary first to rotate or swing end panels 22 and 23 about their respective end hinges and their intermediate hinges from their horizontal inwardly folded positions to their vertical positions. Next, rear panel 21 must be swung outwardly between the vertically positioned end wall panels from its horizontal position to its vertical position. Finally, front panel 20 must be swung outwardly between the then vertically positioned rear and end wall panels from its horizontal position to its vertical position.

In view of the foregoing description, it will be understood that the outer shell of the collapsible container of this invention may be erected and collapsed without requiring any of the outer shell panels to be swung outwardly of their vertical operative positions. As a result of this arrangement, the fluid-tight inner bladder 52 of the container, presently to be described, it is at all times protectively surrounded by the rigid panels of the container outer shell.

Means including tongue and groove type joints are provided for forming releasable connections between the unhinged marginal edges of the front and rear wall panels of the container outer shell and the corresponding unhinged marginal edges of the top and end wall panels of the shell in order to prevent said front and rear panels from being swung outwardly of their vertical operative positions. As shown in FIGS. 7 and 8, such tongue and groove joints may be provided by a plurality of rigid flanges 39 secured near the top and side marginal edges of front panel 29 and rear panel 21, and corresponding rigid flanges 44 secured near the front and rear marginal edges of top panel 24 and near the front and rear marginal edges of each of end panels 2-2 and 23. Each of flanges 39 has an outwardly facing tongue 41 and groove 42 formed near its outer end, and each of the corresponding flanges ill has an inwardly facing tongue 43 and groove 44 formed near its outer end.

As best seen in FIG. 7, the tongues and grooves on the several corresponding flanges are constructed and arranged so that when front and rear panels 24? and 21 are swung outwardly to their vertical operative positions between the then vertically positioned end panels 22 and 23, the outwardly facing tongues 41 on the front and rear panels engage in corresponding ones of grooves 44 on the top and end panels, and, at the same time, the inwardly facing tongues 43 on the top and end wall panels engage in corresponding ones of grooves 42 on the front and rear panels. This engagement of the tongue and groove joints formed along the adjacent unhinged marginal edges of the front, rear, top and end wall panels of the container outer shell not only prevents its front and rear wall panels from being swung outwardly of their vertical positions, but also serves to lock its intermediately hinged end wall panels in their vertical positions, thereby increasing the structural rigidity of the outer shell when the container is in its erect condition.

According to still another novel feature of the invention, the intermediate hinge connections 3'! and 3:; of end panels 22 and 23 are provided by spring-loaded, self-locking hinge means. As shown in FIGS. 9, l0 and 11, such hinge means may comprise a plurality of spaced knuckles 45 formed along the lower edge of the upper section of each panel adapted to interfit with corresponding spaced knuckles as formed along the upper edge of the lower section of each end panel. These interfitting knuckles are hinged together by hinge pins 47, the outer ends of pins 47 being turned back toward one another and engaging the outer surfaces of the upper and lower panel sections on opposite sides of the hinge. Thus, hinge pins 47 act as torsion bars whose springlike action tends to open the hinges and urge the end panels toward their vertical operative positions.

As best seen in FIGS. 10 and 11, knuckles 45 have downwardly facing shoulders 48 adapted to engage corresponding upwardly facing shoulders 49 formed between knuckles 4d, knuckles 46 in turn having upwardly facing shoulders 50 adapted to engage corresponding downwardly facing shoulders 51 formed between knuckles 45 when hinges 37 and 38 are in their fully opened positions. The engagement between the shoulders on the intermediate hinges of end panels 232 and Z3 prevent these panels from buckling outwardly of their vertical positions while the front and rear panels are being swung to and from their collapsed positions.

As previously mentioned, a fluid-tight bladder, indicated generally at 52, is mounted within the collapsible outer shell of the container and is at all times protectively surrounded by the rigid panels of said outer shell. Bladder 52 is rectangular in shape and has thin, sheetlike top, bottom, front, rear and end walls of flexible material such as natural or synthetic rubber, rubberized fabrics, and the like, said bladder Walls being integrally joined together along their adjacent marginal edges.

An important feature of this invention resides in providing means for attaching corresponding walls of inner bladder 52 only to bottom panel 25 and to front panel 20 (the first panel to be swung to stacked position when the outer shell of the container is collapsed) whereby said bladder is constrained, when emptied, to be collapsed to a predetermined configuration within the then erect outer shell in which the unattached top and rear walls 53 and 56 of the bladder are folded inwardly to superposed contacting positions on its attached front and bottom walls 55 and 54, respectively, and the upper rear portion of each of the unattached end walls 57 and 58 of the collapsed bladder are folded inwardly to superposed contacting positions on the lower front portion of such end walls (FIGS. 12 and 14).

In the embodiment shown, such attaching means comprises a plurality of fastening means 59 located near each top and bottom corner of bladder front wall 55 and near each rear corner of bladder bottom wall 54, said attaching means being adapted to connect the upper corners of shell front panel 20 with the upper corners of bladder front wall 55, to connect the lower corners of said bladder front wall with the upstanding wall 26 of bottom panel 25 to which front panel 20 is hinged, and to connect the rear corners of bladder bottom wall 54 with the rear corners of shell bottom panel 25 at points inwardly of its upstanding rear and end walls 27, 28 and 29.

As best seen in FIGS. 14 and 15, each of the fastening means 59 embodies a flexible tab 60 cemented, vulcanized or otherwise bonded at its ends to the outer surfaces of the bladder front and bottom walls at the points described above, each of said tabs having a stud-receiving opening 61 intermediate its bonded ends located to register with a corresponding stud-receiving opening 62 formed in the adjacent outer shell panel. A rigid nut plate having a base 63 and a threaded stud 64 is mounted in the space 65 between tab 60 and the outer surface of the bladder wall. Stud 64 extends outwardly through stud-receiving openings 61 and 62, whereby tightening of nut 66 against the outer surface of the shell panel causes tab 60 to be clamped tightly between nut plate base 63 and the inner surface of said shell panel.

Inasmuch as only the front and bottom walls of the bladder are attached to the panels of the container outer shell, the remaining unattached bladder walls are free to collapse downwardly and inwardly as material is withdrawn from the bladder. Thus, when the bladder is emptied, it will assume a position within the erect outer shell in whichthere will be two layers of bladder material (the attached front wall 55 and the unattached top wall 53) folded smoothly against front shell panel 20, and two layers of bladder material (the attached bottom wall 54 and the unattached rear wall 55) folded smoothly against bottom shell panel 25 inwardly of its upstanding walls 26, 27, 28 and 29 which, as will be recalled, define the lateral extent of the open topped cavity 30 formed on the top side of the bottom panel. As is illustrated in FIGS. 12 and 14, this leaves the unattached bladder end walls 57 and 58 in double layers in the shape of right triangles at each end of the erect container outer shell, said right triangles being formed when the upper rear portion of each bladder end wall is folded downwardly and inwardly on its lower front portion during collapsing of the bladder, these end walls being so folded approximately along the diagonals extending between their upper front and lower rear corners.

' According to still another novel feature of the invention, bladder 52 is provided with wall-stiffening means including relatively stiff bars 67 at each of its unattached end walls 57 and 58. In FIGS. 12 and 14, these stiffening bars, which may comprise hollow moldings of rubber or the like having spring steel wires through their centers, are secured as by being cemented, vulcanized or otherwise bonded to the outer surfaces of the bladder end walls and extend diagonally therealong between points near their lower front and rear corners and points near their centers.

One purpose of stiffening bars 67 is to help insure that bladder end walls 57 and 58 will fold inwardly in a predetermined and orderly manner when the front shell panel is swung to its stacked position between the vertically positioned rear and end shell panels. The manner in which bars 67 operate to accomplish their intended function is illustrated in FIG. 13. In that drawing, the letter A represents the upper edge of the front shell panel 20 (and hence the edges of bladder front and top walls 55 and 53, respectively) and A A A A and A represent the various positions assumed by the edge of the panel as it is swung from its vertical position downwardly to its horizontal position. The letter B represents a point on each of bladder end wall panels 57 and 58, the positions of points B which correspond to the positions of point A being shown as B B B B and B As can be seen from the drawing, as the front panel 20 is lowered, the bladder end wall at each end of the container, which is in the form of a right triangle, is in elfect folded in the middle, and, by the time the front panel reaches the horizontal position, the original right triangle consists of two triangles, one folded on top of the other. Thus, stiffening bars 67 constrain the bladder end walls, when the front shell panel is swung from its erect operative position to its collapsed inoperative position, to be buckled inwardly toward one another and smoothly folded between the superposed bladder front and top walls (carried by front shell panel 20) and the superposed bladder bottom and rear walls (lying on the bottom of bottom shell panel 25 and between its upstanding walls 26, 27, 28 and 29). When front panel 20 reaches its collapsed inoperative position, the entire bladder 52 is folded neatly within cavity 30 and protected from any possibility of damage during collapsing of the remaining outer shell panels.

Means including an inlet opening 68 formed near the top of bladder front wall 55 and an outlet opening 69 formed in bladder bottom wall 54 are provided for introducing material into and removing same from bladder 52 when the container is in use. Inlet 6S normally is sealably covered by a cap 70, while outlet 69 has a valve means 71 associated therewith. This arrangement permits liquids and the like to be removed from bladder 52 without allowing air to enter the bladder to replace the liquid. Thus, atmospheric pressure substantially completely collapses bladder 52 when all of the liquid is withdrawn therefrom. As previously described, fastening means 59 control the manner or the configuration in which the bladder so collapses so that it will be properly positioned within the erect outer shell to be folded into the protective cavity 30 when the outer shell is collapsed. As will be understood, although one opening has been provided in each of the bladder front and bottom walls for introducing and removing material from the bladder, more than one opening may be provided in each of these walls or either opening may be eliminated so as to fill and empty the bladder from the same opening without departing from the invention herein described. It also will be understood that material may be introduced into the bladder through bottom wall opening 69, as by using a pump or the like. In such cases, overfilling and/or pressurization of the container can be avoided either by removing cap 70 during the filling operation, thereby permitting material being forced into the container through bottom wall opening 69 to overflow through front wall opening 68 when the bladder has been filled, or by employing a float-operated shut-off type valve for the valve means 71 adapted to close when the material reaches a predetermined level in the bladder.

The container of this invention not only can be used to advantage as a container for liquids, but also can be used as a container for solid materials such as powdered or granular materials and the like. In some applications, it is of great importance to obtain maximum collap'sibility of the container. That is, it is considered necessary that the container in its collapesd condition should occupy the smallest possible space. With the rigid support bases now utilized in presently known collapsible containers, this requirement can present serious problems. For example, if a valve such as the valve 71 must be provided in the bottom of the con tainer, the rigid base must be tall enough so that the valve not only clears the ground at all times but also provides sufficient clearance or access for operating the valve.

These difficulties are overcome according to this invention by providing the container with collapsible base means 72 arranged beneath bottom panel 25 and movable with respect to the bottom panel between erect positions in which the bottom wall of the container (and hence valve 71) is spaced a substantial distance above the ground, and collapsed positions in which the base is fold- 7 ed up adjacent to the bottom wall panel and extendsdownwardly therefrom only by a distance necessary to provide sufiicient space between the ground and bottom wall of the container to accommodate valve 71.

As illustrated in the drawings, such collapsible base means may comprise a plurality of rigid links73 pivotally connected at their upper ends with bottom shell panel 25 and pivotally connected at their lower ends with a pair of opposed support plates 74 and 75. These support plates are freely swingable on their pivotal links in lateral directions between collapsed positions (FIGS. 2, 6 and 8) in which their adjacent edges 76 and 77 are spaced apart, and erected positions (F165. 1, 3, 4, 5, 12 and 13) in which their edges 76 and 77 engage. In this engaged erect position, the links connecting the support plates with bottom panel 25 are angled toward one another, thereby locking the base in its erect position.

From the foregoing it will be seen that this invention is one well adapted to attain all of the ends and objects hereinabove set forth, together with other advantages which are obvious and which are inherent to the apparatus.

t will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the claims.

As many possible embodiments may be made of the invention wtihout departing from the scope thereof, it is to be understood that all matter herein set forth or shown in he accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

The invention having been described, what is claimed is:

1. A collapsible container comprising: an outer shell having top, bottom and side wall panels of rigid material; means for hingedly connecting said side wall panels with said top and bottom wall panels, said side wall panels being swingable about their respective hinged connection between erect positions and collapsed positions stacked in predetermined order between said top and bottom wall panels; a closed flexible bladder mounted within said outer shell; means for attaching said bladder only to the bottom wall panel and to the side wall panel of said shell which is stacked adjacent the bottom panel; and means including an opening in at least one of the attached bladder walls for introducing material into and removing same from the bladder.

2. A collapsible container according to claim 1 further characterized in that the joints between the unhinged marginal edges of adjacent ones of said shell panels are provided by tongue and groove type joints, said tongue and groove joints being engageable when the side wall panels are swung to their erect operative positions for preventing said panels from being swung outwardly of such erect operative positions.

3. A collapsible container comprising: an outer shell having top, bottom, front, rear and end wall panels of relatively rigid material, said top, bottom, front and rear wall panels being of unitary construction and said end wall panels being hinged intermediate their ends; means for hingedly connecting said unitary front and rear wall panels to said bottom wall panel and for hingedly connecting said intermediately hinged end wall panels with both of said top and bottom wall panels, said front, rear and end panels being swingable about their respective hinged connections between vertical positions and horizontal positions stacked in predetermined order between said top and bottom panels, said front panel being the first wall panel to be swung to stacked position when the outer shell is collapsed; a flexible bladder mounted within said outer shell having top, bottom, front, rear and end walls integrally joined together along their adjacent edges; means for attaching the bottom wall and the front wall of said bladder to the bottom wall panel and the front wall panel, respectively, of said outer shell, said attaching means con- 8e straining the bladder, when" emptied, to be collapsed to a predetermined configuration within the erect outer shell iri which-the unattached top and rear walls of the bladder are folded downwardly and inwardly to superposed contacting positionson its attached front and bottom walls,

respectively, and the upper rear portion of each unattached bladder end wall is folded downwardly and inwardly to super-posed contacting position on the lower front portion of such bladder end wall; and means including an opening in at least one of the attached bladder walls for introducing material into and removing same from the bladder when the container is in use.

4. A collapsible container according to claim 3 further characterized in that said bladder is provided with wallstiffening means including a plurality of relatively stiff bars mounted onthe unattached walls of the bladder and extending diagonally therealong' between the points near their lower front and rear corners and points near their centers, said stiffening bars constraining the bladder end walls, upon movement of said front panel from its vertical operative position to its horizontal inoperative position, to be buckled inwardly toward one another and smoothly folded between the superposed front and top walls and the superposed bottom and rear walls of the then collapsed bladder.

5. A collapsible container according to claim 3 further characterized in that the joints between the unhinged' marginal edges of said front and rear wall panels and the corresponding unhinged marginal edges of said top and end wall panels are provided by tongue and groove type joints, said tongue and groove joints being engageable when the front and: rear wall panels are swung to their vertical operative positions for preventing said panels from being swung outwardly of such vertical operative positions.

6. A collapsible container according to claim 3 further characterized in that said attaching means includes a plurality of fastening means located near each upper and lower corner of said bladder front wall and near each rear corner of said bladder bottom wall.

7. A collapsible container comprising: an outer shellhaving a plurality of hingedly interconnected rectilinear panels of rigid material including a top panel, a bottom panel arranged beneath said top panel and having relatively low upstanding rigid side and end' walls extending thereabove near its marginal edges, front and rear panels of unitary construction having their lower ends hingedly connected with the tops of corresponding ones of saidu-pst-anding bottom panel side walls and being sequentially swingable thereon between vertical operative positions and horizontal inoperative positions superposed above said bottom panel with the rear panel stacked on top of the front panel, end panels hinged intermediate their ends and having their lower ends hingedly connected with tops of corresponding ones of said upstanding bottom panel end walls and their upper ends hingedly connected with said top panel near its opposed marginal end edges, said end panels being rotatable about their various hinged connections between vertical operative positions and horizontal inoperative positions buckled inwardly and stacked side by side between said top panel and the then stacked front and rear panels; a fluid-tight bladder of flexible material mounted within said outer shell, said bladder having thin, sheet-like top, bottom, front, rear and end walls integrally joined together along their adjacent edges; fastening means for connecting the rear corners of the bottom wall of said bladder with the rear corners of said bottom panel and for connecting the upper and lower corners of the bladder front wall with the upper corners of said front panel and with the upstanding bottom panel side wall to which the front panel is hinged; bladder wall-stiffening means including a plurality of relatively stiff bars secured to the end walls of the bladder and extending diagonally therealong between points near their lower front and rear 9 corners and points near their centers; and means including an opening in at least one of the bladder front walls and the bladder bottom wall for introducing material into and removing same from the bladder.

8. A collapsible container according to claim 7 further characterized in that said fastening means includes: a plurality of flexible tabs having their ends bonded to the outer surfaces of said bladder near each upper and lower corner of its front wall and near each rear corner of its bottom wall; and means including a plurality of rigid nut plates for releasably clamping said flexible tabs to the inner surfaces of their adjacent shell panels.

9. A collapsible container according to claim 7 further characterized in that means are provided for forming releasable connections between the nnhinged marginal edges of said front and rear panels and the corresponding unhinged marginal edges of said top and end panels, said releasable connections including tongue and groove type joints formed along the top and side marginal edges of said front and rear panels and along the corresponding marginal edges of said top and end panels, the tongues of said joints engaging in their corresponding grooves when the front and rear panels are swung to their vertical positions between the then vertically disposed end panels, thereby preventing the front and rear panels from being swung outwardly of their vertical positions and at the same time locking the end panels in their vertical positions.

10. A collapsible container according to claim 9 further characterized in that the hinged connections intermediate the upper and lower ends of said end panels are provided by self-locking hinge means having oppositely facing shoulders on their upper and lower leaves constructed and arranged so that corresponding ones of the shoulders engage when the end panels are rotated from their horizontal positions to their vertical positions, thereby preventing these panels from buckling outwardly of such vertical positions.

11. A collapsible container according to claim 9 further characterized in that said self-locking hinge means are provided with spring means acting between the upper and lower leaves of such hinge means to urge the end panels in directions from their horizontal positions toward their vertical positions.

12. A collapsible container comprising: a collapsible outer shell having top, bottom and side wall panels hingedly interconnected for movement with respect to one another between erect positions and collapsed superposed positions; a collapsible bladder mounted in said outer shell; valve means mounted on said bottom panel and extending therebelow a relatively short distance, said valve means communicating with the interior of said bladder; and collapsible base means arranged beneath said bottom panel and at all times extending therebelow a greater distance than said valve means, said collapsible base means including a pair of support plates adapted to rest on the ground or the like and a plurality of rigid links pivotally connected at their upper ends With. said bottom panel and pivotally connected at their lower ends with corresponding ones of said plates, said plates being laterally swingable on their respective pivoted links between collapsed positions spaced apart from one another and retracted upwardly to points relatively close to said bottom panel and erect positions engaging one another and extending downwardly to points further from said bottom panel.

13. A liner for use in cubical containers of the type having a collapsible outer shell provided by a plurality of hingedly connected panels of rigid material, the side wall panels of said outer shell being swingable in predetermined sequence between erect operative positions and collapsed inoperative positions, said liner comprising: a collapsible fluid-tight bladder having thin, sheet-like top, bottom and side walls; and fastening means carried by said bladder for attaching only its bottom wall and one of its side walls to said bottom panel and to the side panel of said shell first to be swung to collapsed position, said fastening means constraining the bladder, when mounted in said outer shell, to be collapsed within the shell in a predetermined manner effective to cause the unattached top and side walls of the bladder to be folded inwardly against its attached side and bottom walls, respectively.

14. A container liner according to claim 13 further characterized in that said fastening means includes a plurality of flexible tabs bonded to the outer surfaces of the bladder near each top and bottom corner of its said one side wall and near each rear corner of its bottom wall.

15. A liner for use in containers of the type having collapsible outer shells provided by a plurality of panels of rigid materials hingedly interconnected in such a manner that first the front panel, then the rear panel and finally the opposed end panels of the outer shell may be sequentially folded inwardly during collapsing operations from vertical operative positions to horizontal inoperative positions stacked in predetermined order between the top and bottom panels of the shell, sad liner comprising: a flexible fluid-tight bladder having thin, sheet-like top, bottom, front, rear and end walls integrally joined together along their adjacent edges, said bladder walls having initial dimensions substantially equal to the dimensions of corresponding ones of said outer shell panels; fastening means positioned adjacent each upper and lower corner of the front wall of the bladder and near each rear corner of its bottom wall for attaching said front and bottom walls of the bladder to said front and bottom panels, respectively, of the outer shell, said fastening means constraining the bladder when mounted in operative position, to be collapsed to a predetermined configuration within the erect outer shell in which the unattached top and rear walls of the bladder are folded inwardly to superposed contacting positions on its attached front and bottom walls, respectively, and the upper rear portion of each unattached bladder end wall is folded inwardly to superposed contacting positions on its lower front portion, the superposed portions of the bladder end walls forming right triangles at each end of the collapsed bladder; and means including openings in the front and bottom walls of the bladder for introducing material into and removing same from the bladder when the container is in use.

16. A container liner according to claim 15 further characterized in that said bladder is provided with wallstiffening means including a plurality of relatively stiff bars secured to and extending diagonally along the end walls of the bladder between points near their lower front and rear corners and points near their centers, said stiffening bars constraining the superposed triangular-shaped portions of the bladder end walls, upon movement of the front panel of the container outer shell from its vertical to its horizontal position, to be buckled inwardly toward one another and smoothly folded between the superposed front and top walls and the superposed bottom and rear walls of the then collapsed bladder.

Frerking Aug. 20, 1957 Potter Sept. 13, 1960 

1. A COLLAPSIBLE CONTAINER COMPRISING: AN OUTER SHELL HAVING TOP, BOTTOM AND SIDE WALL PANELS OF RIGID MATERIAL; MEANS FOR HINGEDLY CONNECTING SAID SIDE WALL PANELS WITH SAID TOP AND BOTTOM WALL PANELS, SAID SIDE WALL PANELS BEING SWINGABLE ABOUT THEIR RESPECTIVE HINGED CONNECTIONS BETWEEN ERECT POSITIONS AND COLLAPSED POSITIONS STACKED IN PREDETERMINED ORDER BETWEEN SAID TOP AND BOTTOM WALL PANELS; A CLOSED FLEXIBLE BLADDER MOUNTED WITHIN SAID OUTER SHELL; MEANS FOR ATTACHING SAID BLADDER ONLY TO THE BOTTOM WALL PANEL AND TO THE SIDE WALL PANEL OF SAID SHELL WHICH IS STACKED ADJACENT THE BOTTOM PANEL; AND MEANS INCLUDING AN OPENING IN AT LEAST ONE OF THE ATTACHED BLADDER WALLS FOR INTRODUCING MATERIAL INTO AND REMOVING SAME FROM THE BLADDER. 